Differences in proleptic and epicormic shoot structures in relation to water deficit and growth rate in almond trees (Prunus dulcis)

UMR 1334 AGAP : Equipe AFEF "Architecture et Fonctionnement des Espèces fruitières" ; Team AFFS "Architecture and Functioning of Fruit Species"International audienceBackground and Aims Shoot characteristics differ depending on the meristem tissue that they originate from and environmental conditions during their development. This study focused on the effects of plant water status on axillary meristem fate and flowering patterns along proleptic and epicormic shoots, as well as on shoot growth rates on 'Nonpareil' almond trees (Prunus dulcis). The aims were (1) to characterize the structural differences between pro-leptic and epicormic shoots, (2) to determine whether water deficits modify shoot structures differently depending on shoot type, and (3) to determine whether shoot structures are related to shoot growth rates. Methods A hidden semi-Markov model of the axillary meristem fate and number of flower buds per node was built for two shoot types growing on trees exposed to three plant water status treatments. The models segmented observed shoots into successive homogeneous zones, which were compared between treatments. Shoot growth rates were cal-culated from shoot extension measurements made during the growing season. Key Results Proleptic shoots had seven successive homogeneous zones while epicormic shoots had five zones. Shoot structures were associated with changes in growth rate over the season. Water deficit (1) affected the occurrence and lengths of the first zones of proleptic shoots, but only the occurrence of the third zone was reduced in epicormic shoots; (2) had a minor effect on zone flowering patterns and did not modify shoot or zone composition of axillary meristem fates; and (3) reduced growth rates, although patterns over the season were similar among treatments. Conclusions Two meristem types, with different latency durations, produced shoots with different growth rates and distinct structures. Differences between shoot type structure responses to water deficit appeared to reflect their onto-genetic characteristics and/or resource availability for their development. Tree water deficit appeared to stimulate a more rapid progression through ontogenetic states

Howard walnut trees can be brought into bearing without annual pruning

In traditionally managed Howard walnut orchards, trees are pruned annually during the orchard development phase, an expensive operation in terms of labor and prunings disposal costs. Our observations and some prior research by others had suggested that pruning may not be necessary in walnut. In a trial of pruned and unpruned hedgerow trees over 8 years, beginning a year after planting, we documented canopy growth, tree height, yield and nut quality characteristics and also the effects of fruit removal. Pruning altered canopy shape but did not lead to increases in canopy development, yield or nut quality. Although fruit removal stimulated more vegetative growth in both the pruned and unpruned treatments, fruit removal did not result in an increase in midday canopy photosynthetically active radiation interception or cumulative yield when fruit removal was stopped after year 4. After 8 years, there were no significant differences in tree height, nut quality or cumulative yield among any of the treatments, which suggests that not pruning young Howard orchards could provide a net benefit to growers

Effect of drying process on lemon verbena (Lippia citrodora Kunth) aroma and infusion sensory quality

Artículo de publicación ISI.Lemon verbena leaves are used as herbal infusion due to their aromatic, digestive and antispasmodic properties. The aim of the present study was to determine the sensory quality of lemon verbena infusions prepared with fresh leaves, dried leaves at 30 C and 60 C. Infusion aroma and taste was determined through a trained sensory panel and an electronic nose (e-nose). Infusion acceptability was evaluated through a consumer test. All drying treatments on day 0 were grouped together regarding the e-nose determination. ‘Floral’ descriptors were related to leaves not submitted to store. When the leaves were stored for 30 days, aroma attributes were lost. Differences on the infusion acceptability were ascribable to the drying method. Infusions prepared with fresh leaves showed the highest acceptability. E-nose could be used as a reliable tool for characterising the quality of aromatic herbs

Determination of harvest maturity of D'Agen plums using the chlorophyll absorbance index

The objective determination of the optimal harvest date for plums intended either for industrial processing or for consumption as fresh fruit is a fundamental concern of the fruit industry. A portable visible/near infrared (Vis/NIR) spectroscopic device was used to sort D'Agen plums harvested around the traditional commercial harvest date. The chlorophyll absorbance index was found to be capable of segregating plums into classes of maturity according to various concentrations of soluble solids and fruit compression strenght values. Fruits with a chlorophyll absorbance index value of less than 1.59 showed no differences in flesh firmness. Plums harvested with chlorophyll absorbance index values of 1.20-1.29 had a fruit compression strenght of 1.25 N and a soluble solids concentration of 23.3%. Both of these values correspond to adequate thresholds for harvesting plums for industrial purposes. The chlorophyll absorbance index may be valuable in allowing the identification of high-quality plums either for fresh consumption or industrial processing.La determinación objetiva del momento óptimo de cosecha de las ciruelas europeas, destinadas tanto para el consumo en fresco y la agroindustria, es una preocupación fundamental para la industria frutícola. Se utilizó un dispositivo espectroscópico Vis/NIR para la clasificación de ciruelas D'Agen cosechadas en torno a la fecha de cosecha comúnmente usada por la industria local. El índice de absorción de clorofila demostró ser capaz de separar los sólidos solubles y la fuerza de compresión de la fruta en las diferentes clases de madurez. La fruta clasificada con un índice de absorbancia de la clorofila menor a 1,59 no mostró diferencias en la firmeza de la pulpa. Las ciruelas cosechadas con un índice de absorbancia de la clorofila entre 1,20-1,29 presentaron una fuerza de compresión de 1,25 N y 23,3% de concentración de sólidos solubles, siendo estos valores umbrales adecuados para la cosecha de ciruelas para fines industriales. El índice de absorción de la clorofila representa un valioso índice que permitiría obtener ciruelas de alta calidad tanto para el consumo en fresco o procesamiento industrial

POSTHARVEST SENSORY AND PHENOLIC CHARACTERIZATION OF 'ELEGANT LADY' AND 'CARSON' PEACHES

High quality fruits are increasingly demanded along with the need to ensure this attribute to consumers. Thus, this study was aimed at characterizing a melting ('Elegant Lady') and a non-melting flesh ('Carson') peach ( Prunus persica (L.) Batsch) varieties by considering both their bioactive compound contribution and their sensory quality in ripe fruit at harvest and after a prolonged period of cold storage. Cultivars were evaluated at harvest (F0) and after 30 d of cold storage (F30), as well as after a maturation period at 20 °C for both F0 and F30 (R0 and R30, respectively). Fruit weight, flesh firmness, soluble solid content (SSC), titratable acidity (TA), and background color (Hue) were recorded at each stage. Furthermore, total phenol content was measured and a phenolic characterization by HPLC (High-Performance Liquid Chromatography) was performed for both varieties to detect the major low molecular weight phenolic compounds present in the fruit. Finally, a trained panel assessed the main sensorial parameters at R0 and R30. Total phenol content did not change significantly as a result of cold storage and differences were probably attributed only to genotype. Low molecular weight phenolic compounds were detected in 'Elegant Lady' and 'Carson', 15 and 12, respectively; (+)-catechin was the major compound found in both cultivars, but in higher concentrations in 'Elegant Lady'. In the phenolic characterization, 'Elegant Lady' was observed more closely than 'Carson' for flavonoids. After 30 d of cold storage, 'Elegant Lady' was unacceptable for consumption due to the appearance of physiological disorders such as wooliness while 'Carson' showed a mean score within the acceptability range

Identificación de segmentos de mercado y preferencias hacia dos variedades de durazno fresco: una aproximación mediante evaluación in situ en una frutería de Santiago, Chile

Consumer behavior regarding two varieties of fresh peaches was studied in a socioeconomically middle-upper level minimarket. 106 two-phase surveys were conducted. The first part was done through a direct interview when the consumers purchased the fruit; the second when the fruit was consumed. The varietes used were the 'Royal Glory' peach and the 'African Gold' canning peach, chosen because they were so distinct. Descriptive aspects of consumption, sociodemographic traits and purchase attitudes were assessed using multivariate and univariate analyses. A demand characterized by preference to purchase in supermarkets was identified. 25% of all those surveyed were young and distinguished by their inexperience in acquiring fresh peaches. The point of sale was the factor which most determined purchase behavior, followed the variety of peach, with supermarkets and the "African Gold" variety being the most preferred. The willingness to pay for desired attributes had the lowest values

Characterization of texture attributes of raw almond using a trained sensory panel

Introduction. Texture parameters are important factors for characterizing the sensory quality of raw almonds; nevertheless there is scarce literature that explores sensory differences among cultivars. The aim of this study was to characterize quality attributes of different raw almond cultivars. Materials and methods. The almond cultivars ‘Nonpareil’, ‘Mission’, ‘Supernova’, ‘Tuono’, ‘Ferragnès’ and ‘Marcona’ were used to characterize their industrial and sensory quality attributes. A panel of 14 assessors with previous experience in testing stone fruit was specifically trained on descriptive analysis for determining quality and particularly texture of raw almonds. Results and discussion. A direct relationship was observed between kernel yield and shell fracture resistance; the American cultivars ‘Nonpareil’, and ‘Mission’ showed more minor shell fracture resistance than the European. ‘Tuono’ stood out for being tasty, crunchy and hard, whereas ‘Marcona’ was noted for its color intensity, crispness and hardness; but it lacked taste. ‘Supernova’ was described as tasty. Conclusion. A 5-h training period proved to be adequate for characterizing raw almond cultivars. The panel was able to discriminate between cultivars and segregate ‘Nonpareil’ and ‘Mission’ from the other cultivars in terms of texture attributes

Identificación de segmentos de mercado y preferencias hacia dos variedades de durazno fresco: una aproximación mediante evaluación in situ en una frutería de Santiago, Chile

Published by Asociación de Economistas Agrarios de Chileconjoint analysis, market segmentation, consumer preference, willingness to pay, peach, fresh fruit, Consumer/Household Economics, Marketing,